U.S. patent application number 11/654565 was filed with the patent office on 2007-08-16 for substrate processing method, substrate processing apparatus, and manufacturing method of semiconductor device.
Invention is credited to Kei Hayasaki, Shinichi Ito, Daisuke Kawamura, Kentaro Matsunaga, Eishi Shiobara, Tomoyuki Takeishi.
Application Number | 20070190462 11/654565 |
Document ID | / |
Family ID | 38368978 |
Filed Date | 2007-08-16 |
United States Patent
Application |
20070190462 |
Kind Code |
A1 |
Shiobara; Eishi ; et
al. |
August 16, 2007 |
Substrate processing method, substrate processing apparatus, and
manufacturing method of semiconductor device
Abstract
A substrate processing method including while a liquid is
supplied between a processing target substrate to be applied with
exposure treatment and a projection optical system of an exposure
apparatus for carrying out the exposure treatment, prior to
providing a resist film on a first main face of the processing
target substrate that is provided for liquid immersion exposure for
carrying out the exposure treatment at a side to be applied with
the exposure treatment, selectively applying at least hydrophobic
treatment with respect to a region in a predetermined range from a
peripheral rim part of a second main face opposite to the first
main face.
Inventors: |
Shiobara; Eishi;
(Yokohama-shi, JP) ; Matsunaga; Kentaro;
(Kawasaki-shi, JP) ; Kawamura; Daisuke;
(Yokohama-shi, JP) ; Takeishi; Tomoyuki;
(Yokkaichi-shi, JP) ; Hayasaki; Kei;
(Kamakura-shi, JP) ; Ito; Shinichi; (Yokohama-shi,
JP) |
Correspondence
Address: |
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER;LLP
901 NEW YORK AVENUE, NW
WASHINGTON
DC
20001-4413
US
|
Family ID: |
38368978 |
Appl. No.: |
11/654565 |
Filed: |
January 18, 2007 |
Current U.S.
Class: |
430/311 |
Current CPC
Class: |
G03F 7/70341 20130101;
Y10S 430/162 20130101 |
Class at
Publication: |
430/311 |
International
Class: |
G03F 7/20 20060101
G03F007/20 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 20, 2006 |
JP |
2006-013061 |
Claims
1. A substrate processing method comprising: while a liquid is
supplied between a processing target substrate to be applied with
exposure treatment and a projection optical system of an exposure
apparatus for carrying out the exposure treatment, prior to
providing a resist film on a first main face of the processing
target substrate that is provided for liquid immersion exposure for
carrying out the exposure treatment at a side to be applied with
the exposure treatment, selectively applying at least hydrophobic
treatment with respect to a region in a predetermined range from a
peripheral rim part of a second main face opposite to the first
main face.
2. The method according to claim 1, wherein the hydrophobic
treatment is applied to a region excluding a center part of the
second main face.
3. The method according to claim 1, wherein a hydrophobic treating
agent for use in the hydrophobic treatment is an organic silicon
compound.
4. The method according to claim 1, wherein a hydrophobic treating
agent for use in the hydrophobic treatment is a fluorocarbon-based
compound.
5. The method according to claim 1, wherein a liquid containing a
hydrophobic treating agent for use in the hydrophobic treatment is
supplied to the second main face of the processing target
substrate, or the second main face of the processing target
substrate is exposed to a gas containing the hydrophobic treating
agent, thereby carrying out the hydrophobic treatment.
6. The method according to claim 1, wherein the hydrophobic
treatment is carried out while heat treatment is applied to the
processing target substrate at a temperature of 80.degree. C. or
more and 200.degree. C. or less.
7. The method according to claim 1, further comprising: applying
heat treatment to the processing target substrate at a temperature
equal to or greater than 100.degree. C. after carrying out the
hydrophobic treatment.
8. A substrate processing apparatus comprising: a substrate housing
chamber in which a processing target substrate to be applied with
exposure treatment is housed prior to providing a resist film on a
first main face at a side at which the exposure treatment is
applied; a substrate support unit which exposes a region in a
predetermined range from a peripheral rim part of a second main
face opposite to at least the first main face in the substrate
housing chamber, and supports the processing target substrate; and
a substrate treating agent supply device which supplies a
hydrophobic treating agent into the substrate housing chamber.
9. The apparatus according to claim 8, further comprising: a
hydrophobic treating agent shielding mechanism which covers a
center part of the second main face in the substrate housing
chamber.
10. The apparatus according to claim 8, further comprising: a
heating device which heats the processing target substrate in the
substrate housing chamber.
11. The apparatus according to claim 10, wherein the substrate
support unit supports the processing target substrate while a gap
between the processing target substrate and the heating device is
spaced by 1 mm or more.
12. The apparatus according to claim 10, wherein the heating device
is provided in the vicinity of the hydrophobic treating agent
shielding mechanism.
13. A manufacturing method of a semiconductor device wherein the
method including a liquid immersion exposure method for carrying
out exposure treatment while supplying a liquid between a
processing target substrate to be applied with the exposure
treatment and a projection optical system of an exposure device for
carrying out the exposure treatment, comprising: providing a resist
film on which a predetermined resist pattern is formed by the
exposure treatment on a first main face of the processing target
substrate at a side to be applied with the exposure treatment;
providing a cover film on the resist film; and selectively applying
the exposure treatment via a mask to the processing target
substrate having the cover film provided thereon, and prior to
providing the resist film on the first main face, selectively
applying at least hydrophobic treatment to a region in a
predetermined range from a peripheral rim part of a second main
face opposite to the first main face of the processing target
substrate.
14. The method according to claim 13, wherein the hydrophobic
treatment is applied to a region excluding a center part of the
second main face.
15. The method according to claim 13, wherein a hydrophobic
treating agent for use in the hydrophobic treatment is an organic
silicon compound.
16. The method according to claim 13, wherein a hydrophobic
treating agent for use in the hydrophobic treatment is a
fluorocarbon-based compound.
17. The method according to claim 13, wherein a liquid containing a
hydrophobic treating agent for use in the hydrophobic treatment is
supplied to the second main face of the processing target
substrate, or the second main face of the processing target
substrate is exposed to a gas containing the hydrophobic treating
agent, thereby carrying out the hydrophobic treatment.
18. The method according to claim 13, wherein the hydrophobic
treatment is carried out while heat treatment is applied to the
processing target substrate at a temperature of 80.degree. C. or
more and 200.degree. C. or less.
19. The method according to claim 13, further comprising: applying
heat treatment to the processing target substrate at a temperature
equal to or greater than 100.degree. C. after carrying out the
hydrophobic treatment.
20. A manufacturing method of a semiconductor device wherein the
method including a liquid immersion exposure method for carrying
out exposure treatment while supplying a liquid between a
processing target substrate to be applied with the exposure
treatment and a projection optical system of an exposure device for
carrying out the exposure treatment, comprising: providing a resist
film on which a predetermined resist pattern is formed by the
exposure treatment on a first main face of the processing target
substrate at a side to be applied with the exposure treatment;
providing a cover film on the resist film; and selectively applying
the exposure treatment via a mask to the processing target
substrate having the cover film provided thereon, and prior to
providing the resist film on the first main face, selectively
applying at least hydrophobic treatment to a region in a
predetermined range from a peripheral rim part of a second main
face opposite to the first main face of the processing target
substrate by use of a substrate processing apparatus, the substrate
processing apparatus comprising: a substrate housing chamber in
which a processing target substrate to be applied with exposure
treatment is housed prior to providing a resist film on a first
face at a side to be applied with the exposure; a substrate support
unit which exposes a region in a predetermined range from a
peripheral rim part of a second main face opposite to at least the
first main face in the substrate housing chamber, and supports the
processing target substrate; and a substrate treating agent supply
device which supplies a hydrophobic treating agent into the
substrate housing chamber.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from prior Japanese Patent Application No. 2006-013061,
filed Jan. 20, 2006, the entire contents of which are incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a substrate processing
method, a substrate processing apparatus, and a manufacturing
method of a semiconductor device. In particular, the present
invention relates to a substrate processing method and a substrate
processing apparatus for use in a liquid immersion exposure
process, and a manufacturing method of a semiconductor device with
using the method and the apparatus.
[0004] 2. Description of the Related Art
[0005] Recently, attention has been focused on an exposure method
referred to as a liquid immersion exposure method. The liquid
immersion exposure method is provided as an exposure method for
carrying out patterning on a resist film while a gap between a
projection optical system (projection lens) of an exposure
apparatus and a processing target substrate (exposure target
substrate) to be applied with exposure treatment is filled with a
liquid (immersion liquid) having a high refractive index. The gap
between the projection optical system and the resist film is filled
with an immersion liquid, whereby a deeper focal point can be
obtained. Currently, pure water is generally used as an immersion
liquid. A technique relating to liquid immersion exposure is
disclosed in Jpn. Pat. Appln. KOKAI Publication No. 10-303114.
However, if pure water exists in a resist film shape, there is a
danger that a photoacid generator agent or the like is eluted from
the inside of the resist film into the pure water. If the photoacid
generator agent is eluted from the inside of the resist film into
the pure water, it becomes difficult to properly pattern the resist
film. In order to avoid such a problem, there is proposed a
technique of further providing a cover film on the resist film.
[0006] In a general exposure target substrate (wafer), its
peripheral rim part is formed in an inclined shape such that the
thickness becomes smaller as it goes from a radial inside to a
radial outside of the wafer. Of the peripheral rim part of the
wafer, a portion having an inclination is referred to as a bevel
portion. Of course, the pure water on the wafer is likely to leak
from the bevel portion to the outside of the wafer. If the pure
water leaks out from the top of the wafer, it becomes difficult to
properly carry out liquid immersion exposure. Therefore, in order
to prevent the pure water from leaking out from the bevel portion
at the time of liquid immersion exposure, it is desirable to cover
a region from a center part of the wafer up to the outer face of
the peripheral rim part with the cover film.
[0007] However, in a general liquid immersion type exposure
apparatus, a slight gap always exists between a wafer and a wafer
stage on which the wafer is placed. For this reason, it is very
difficult to completely restrict liquid leakage from the bevel
portion. In addition, there is a high danger that the liquid
leakage from the bevel portion causes a problem that pure water
goes around the back face side of the wafer. In a state in which
the pure water goes around the back face side of the wafer and the
back face side remains wet, which leads contamination of the wafer
stage of the exposure apparatus and quality deterioration of wafers
to be processed later. Finally, in a semiconductor device
manufactured by using such a wafer whose quality deteriorates,
there is a high danger that its performance, quality, reliability
or the like deteriorates.
BRIEF SUMMARY OF THE INVENTION
[0008] According to an aspect of the invention, there is provided a
substrate processing method comprising:
[0009] while a liquid is supplied between a processing target
substrate to be applied with exposure treatment and a projection
optical system of an exposure apparatus for carrying out the
exposure treatment, prior to providing a resist film on a first
main face of the processing target substrate that is provided for
liquid immersion exposure for carrying out the exposure treatment
at a side to be applied with the exposure treatment, selectively
applying at least hydrophobic treatment with respect to a region in
a predetermined range from a peripheral rim part of a second main
face opposite to the first main face.
[0010] According to another aspect of the invention, there is
provided a substrate processing apparatus comprising: a substrate
housing chamber in which a processing target substrate to be
applied with exposure treatment is housed prior to providing a
resist film on a first main face at a side at which the exposure
treatment is applied; a substrate support unit which exposes a
region in a predetermined range from a peripheral rim part of a
second main face opposite to at least the first main face in the
substrate housing chamber, and supports the processing target
substrate; and a substrate treating agent supply device which
supplies a hydrophobic treating agent into the substrate housing
chamber.
[0011] According to still another aspect of the invention, there is
provided a manufacturing method of a semiconductor device wherein
the method including a liquid immersion exposure method for
carrying out exposure treatment while supplying a liquid between a
processing target substrate to be applied with the exposure
treatment and a projection optical system of an exposure device for
carrying out the exposure treatment, comprising: providing a resist
film on which a predetermined resist pattern is formed by the
exposure treatment on a first main face of the processing target
substrate at a side to be applied with the exposure treatment;
providing a cover film on the resist film; and selectively applying
the exposure treatment via a mask to the processing target
substrate having the cover film provided thereon, and prior to
providing the resist film on the first main face, selectively
applying at least hydrophobic treatment to a region in a
predetermined range from a peripheral rim part of a second main
face opposite to the first main face of the processing target
substrate.
[0012] According to yet another aspect of the invention, there is
provided a manufacturing method of a semiconductor device wherein
the method including a liquid immersion exposure method for
carrying out exposure treatment while supplying a liquid between a
processing target substrate to be applied with the exposure
treatment and a projection optical system of an exposure device for
carrying out the exposure treatment, comprising: providing a resist
film on which a predetermined resist pattern is formed by the
exposure treatment on a first main face of the processing target
substrate at a side to be applied with the exposure treatment;
providing a cover film on the resist film; and selectively applying
the exposure treatment via a mask to the processing target
substrate having the cover film provided thereon, and prior to
providing the resist film on the first main face, selectively
applying at least hydrophobic treatment to a region in a
predetermined range from a peripheral rim part of a second main
face opposite to the first main face of the processing target
substrate by use of a substrate processing apparatus, the substrate
processing apparatus comprising: a substrate housing chamber in
which a processing target substrate to be applied with exposure
treatment is housed prior to providing a resist film on a first
face at a side to be applied with the exposure; a substrate support
unit which exposes a region in a predetermined range from a
peripheral rim part of a second main face opposite to at least the
first main face in the substrate housing chamber, and supports the
processing target substrate; and a substrate treating agent supply
device which supplies a hydrophobic treating agent into the
substrate housing chamber.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0013] FIG. 1 is a view schematically depicting a general
configuration of a liquid immersion type exposure apparatus
according to a first embodiment;
[0014] FIG. 2 is a view schematically depicting a general
configuration of a substrate processing section of a substrate
processing apparatus according to the first embodiment;
[0015] FIG. 3 is a view schematically depicting a general
configuration of a substrate treating agent supply section of the
substrate processing apparatus according to the first
embodiment;
[0016] FIG. 4 is a flow chart showing a substrate processing method
according to the first embodiment;
[0017] FIG. 5A is a plan view showing a substrate applied with
substrate processing according to the first embodiment, as seen
from the back side;
[0018] FIG. 5B is a sectional view showing the substrate applied
with substrate processing according to the first embodiment;
[0019] FIG. 6 is a sectional view showing a substrate according to
Comparative Example against the first embodiment;
[0020] FIG. 7A is a plan view showing a substrate applied with
substrate processing according to a second embodiment, as seen from
the back side;
[0021] FIG. 7B is a sectional view showing the substrate applied
with substrate processing according to the second embodiment;
and
[0022] FIG. 8 is a flow chart showing a substrate processing method
according to a third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Now, embodiments according to the present invention will be
described with reference to the accompanying drawings.
FIRST EMBODIMENT
[0024] First, a first embodiment according to the present invention
will be described with reference to FIGS. 1 to 5B. FIG. 1 is a view
schematically depicting a general configuration of a liquid
immersion type exposure apparatus according to the first
embodiment. FIG. 2 is a view schematically depicting a general
configuration of a substrate processing section of a substrate
processing apparatus according to the first embodiment. FIG. 3 is a
view schematically depicting a general configuration of a substrate
treating agent supply section of the substrate processing apparatus
according to the first embodiment. FIG. 4 is a flow chart showing a
substrate processing method according to the first embodiment. FIG.
5A is a plan view showing a substrate applied with substrate
processing according to the first embodiment, as seen from the back
side. FIG. 5B is a sectional view showing the substrate applied
with substrate processing according to the first embodiment.
[0025] In the present embodiment, prior to providing a resist film
on a main face of a processing target substrate to be applied with
exposure treatment at a side to be applied with exposure treatment,
hydrophobic treatment is applied to a main face opposite to the
main at the side to be applied with exposure treatment. Now, a
specific and detailed description will be given below.
[0026] First, with reference to FIG. 1, a liquid immersion type
exposure apparatus 1 according to the embodiment will be given
below. The liquid immersion type exposure apparatus 1 shown in FIG.
1 is one kind of liquid immersion type exposure apparatus referred
to as a so-called scan type.
[0027] As shown in FIG. 1, the liquid immersion type exposure
apparatus 1 is equipped with a reticule stage 3 serving as a
reticule support unit for supporting a reticule 2. In addition,
although not shown, the liquid immersion type exposure apparatus 1
is equipped with an exposure light source (illumination light
source) for generating exposure light (illumination light) and an
illumination lens system (illumination optical system) for guiding
the illumination light generated by the illumination light source
to the reticule 2. The reticule stage 3 is arranged below an
optical path of the illumination light source and the illumination
lens system. Concurrently, the reticule stage 3 is set to be
movable in a parallel forward direction or in a parallel opposite
direction along a direction orthogonal to an optical axis of the
liquid immersion type exposure apparatus 1. The reticule 2 is
provided on a main face (surface, top face) at a side opposite to
the illumination light source and the illumination lens system of
the reticule stage 3. In addition, although not shown, at least one
pattern (mask pattern) having a predetermined shape formed to be
exposed on a surface 5a of an exposure target substrate 5 is formed
on the reticule 2.
[0028] In addition, the liquid immersion type exposure apparatus 1
is equipped with a projection lens system (projection optical
system) 4 for guiding the exposure light having passed through
(having transmitted) the reticule 2 to the surface 5a of the
exposure target substrate 5. The projection lens system 4 is
disposed downwardly of an optical path of the reticule stage 3.
[0029] In addition, the liquid immersion type exposure apparatus 1
is equipped with an exposure target substrate stage (wafer stage) 6
serving as an exposure target substrate support element (wafer
support element) for supporting the exposure target substrate
(wafer, semiconductor substrate) 5 applied with exposure
processing. The wafer stage 6 is disposed downwardly of an optical
path of the projection lens system 4. In addition, the wafer stage
6 is set to be movable in a parallel forward direction or in a
parallel opposite direction together with the wafer 5 along a
direction orthogonal to an optical axis of the liquid immersion
type exposure apparatus 1, as in the reticule stage 3. In this
manner, the wafer stage 6 and the wafer 5 placed (mounted) on the
wafer stage 6 can relatively move with respect to the projection
lens system 4. In addition, from an opposite point of view, the
projection lens system 4 can relatively move with respect to the
wafer stage 6 and the wafer 5 placed on the wafer stage 6. The
wafer 5 is placed on a main face (surface, top face) of a side
opposite to the projection lens system 4 of the wafer stage 6.
[0030] In addition, on a surface of the wafer stage 6, there is
provided a support plate (support member) 7 serving as an exposure
target substrate holding element (wafer holding element) for
holding the wafer 5 so as not to be displaced when the wafer 5
moves together with the wafer stage 6. The support plate 7 is
provided to surround a peripheral rim part (outer rim part) 5b of
the wafer 5.
[0031] In addition, at a distal end part 4a of the projection lens
system 4, there is provided a fence 8 serving as a liquid holding
element (immersion liquid holding element) for holding a liquid
(immersion liquid) for exposure processing supplied between the
projection lens system 4 and the wafer 5, in a desired region on
the surface 5a of the wafer 5. In addition, laterally of the
projection lens system 4, there is provided a liquid
supply/discharge device (immersion liquid supply/discharge device)
9 consisting of a liquid supply device 9a for supplying a liquid
into the fence 8 and a liquid discharge device 9b for discharging a
liquid from the inside of the fence 8. In the present embodiment,
the apparatus is set such that a liquid is supplied into the fence
8 from the liquid supply device 9a disposed at the right side of
the projection lens system 4 shown in FIG. 1. In addition, the
apparatus is set such that a liquid is discharged from the inside
of the fence 8 by means of the liquid discharge device 9b disposed
at the left side of the projection lens system 4. In the present
embodiment, as an immersion liquid (first chemical), as in a
general liquid immersion exposure process, pure water is used.
Therefore, the liquid supply/discharge device 9 is also merely
referred to as a water supply/discharge device. Similarly, the
liquid supply device 9a and the liquid discharge device 9b each are
merely referred to as a water supply device 9a and a water
discharge device 9b.
[0032] With such settings, at least at the time of carrying out
liquid immersion exposure, a space enclosed by the fence 8 between
the distal end part 4a of the projection lens system 4 and the
surface 5a of the wafer 5 is filled with a liquid film (water film)
made of pure water. A region filled with the water film between the
projection lens system 4 and the wafer 5 is also referred to as a
liquid immersion region. Concurrently, the distal end part 4a of
the projection lens system 4 is also referred to as a liquid
immersion head. In FIG. 1, liquid immersion is not shown in order
to clarify drawings.
[0033] Further, although not shown, at the side of the projection
lens system 4, there is provided an alignment mark detecting device
for detecting an alignment mark. In this alignment mark detecting
device as well, as in the projection lens system 4, the wafer stage
6 relatively moves with respect to the projection lens system 4,
whereby the detecting device can relatively move with respect to
the wafer stage 6 and the wafer 5. Alignment mark detection is
carried out prior to applying liquid immersion exposure processing
to the wafer 5, in order to enhance exposure precision.
[0034] Although not shown, the illumination light emitted from the
illumination light source arrives at the reticule 2 through the
illumination lens system. The illumination light having arrived at
the reticule 2 passes through a mask pattern formed on the reticule
2, whereby the mask pattern is molded into a predetermined shape.
Then, the illumination light (exposure light) formed in the
predetermined pattern shape is incident to the projection lens
system 4. The exposure light incident to the projection lens system
4 is emitted from the distal end part (liquid immersion head) 4a of
the projection lens system 4, and then, passes through the liquid
immersion region and arrives at a desired irradiation region
(exposure region) set on the surface 5a of the wafer 5. In more
detail, a mask pattern image is exposed and projected onto a
surface of a photo resist (not shown) provided on the surface 5a of
the wafer 5, and a mask pattern latent image is formed therein.
That is, liquid immersion exposure processing is applied to the
surface 5a of the wafer 5.
[0035] Now, with reference to FIGS. 2 and 3, a substrate processing
apparatus 10 according to the present embodiment will be described
here. The substrate processing apparatus 10 is composed of a
substrate processing section 10a and a substrate treating agent
supply section 10b.
[0036] First, with reference to FIG. 2, the substrate processing
section 10a will be described here. The substrate processing
section 10a is specifically provided as a hydrophobic treatment
section which applies hydrophobic treatment to the wafer 5.
[0037] As shown in FIG. 2, the hydrophobic treatment section 10a is
equipped with a chamber 11 serving as a substrate housing chamber
for housing the wafer 5. The wafer 5 is housed in the chamber 11
prior to providing a resist film 32 described later on the surface
5a that is a first main face at a side to be applied with exposure
treatment. In the chamber 11, there are provided a plurality of
pins 12 serving as a substrate support unit for exposing and
supporting a region in a predetermined range from at least a
peripheral rim part 5b of the wafer 5, of a back face 5c that is a
second main face opposite to the surface 5a of the wafer 5. In the
present embodiment, three pins 12 are concentrically installed. In
FIG. 2, however, only two of the three pins 12 are shown in order
to clarify drawings. The wafer 5 is placed on each of the pins 12
with its back face 5c oriented downward.
[0038] In the chamber 11, a hot plate (heating device) 13 for
heating the wafer 5 from the side of the back face 5c is installed
at a position opposite to the back face 5c of the wafer 5 placed on
each of the pins 12. The hot plate 13 can heat the wafer 5 such
that a temperature of the back face 5c is in the range of about
80.degree. C. or more and 200.degree. C. or less.
[0039] As indicated by the dashed line shown in FIG. 2, a
configuration may be provided such that a hydrophobic treating
agent shielding mechanism 14 is installed at a position that covers
a center part of the back face 5c of the wafer 5 at a side opposite
to the back face 5cof the wafer 5 placed on each of the pins 12. A
technique of utilizing the hydrophobic treating agent shielding
mechanism 14 will be described in a second embodiment described
later.
[0040] A hydrophobic treating agent inlet port 15 and an intake
port 16 are formed in the chamber. The hydrophobic treating agent
inlet port 15 introduces into the chamber 11 the hydrophobic
treating agent supplied from the substrate treating agent supply
section 10b described later, and the intake port 16 introduces an
inert gas such as air or nitrogen into the chamber 11. The chamber
11 also has an exhaust port 17 for discharging the hydrophobic
treating agent, air, and various inert gases introduced into the
chamber 11 to the outside of the chamber 11. Further, a diffusion
plate 18 is provided at an upper part of the chamber 11. The
diffusion plate 18 substantially uniformly diffuses in the chamber
11 the atmosphere introduced into the chamber 11. Although not
shown, a pump is provided at a secondary side (outside, downstream
side) of the exhaust port 17, the inside of the substrate housing
chamber is vacuum-drawn, whereby a design may be made to increase
discharge efficiency.
[0041] In FIG. 2, the hydrophobic treating agent inlet port 15 is
formed at the upper part of the chamber 11 and a design is made
such that an atmosphere such as a hydrophobic treating agent is
introduced through the surface (top face) 5a and the side face of
the wafer 5. However, a position of the hydrophobic treating agent
inlet port 15 is not limited to the position shown in FIG. 2. The
hydrophobic treating agent inlet port 15 may be formed at a
position at which charge efficiency of the hydrophobic treating
agent into the chamber 11 is good. Such a design also applies to
the intake port 16 and the exhaust port 17. The intake port 16 may
be formed at a position at which displacement efficiency of the
hydrophobic treating agent in the chamber with the inert gas is
good. In addition, the exhaust port 17 may be provided at a
position at which discharge efficiency of the hydrophobic treating
agent from the inside of the chamber 11 to the outside of the
chamber 11 is good.
[0042] Now, with reference to FIG. 3, a description will be given
with respect to the substrate treating agent supply section 10b of
the substrate processing apparatus 10 according to the
embodiment.
[0043] The substrate treating agent supply section 10b is
specifically provided as a hydrophobic treating agent supply device
for supplying a hydrophobic treating agent into the chamber 11 of
the hydrophobic treatment section 10a described previously. The
hydrophobic treating agent supply device 10b includes a chemical
supply section 21 supplied with a chemical 22 of a hydrophobic
treating agent and a hydrophobic atmosphere producing section 2 for
producing an atmosphere including the hydrophobic treating agent.
As shown in FIG. 3, the chemical 22 of the hydrophobic treating
agent is supplied to, and is stored in, the chemical supply section
21. Thus, the chemical supply section 21 is also referred to as a
chemical bottle (hydrophobic treating agent bottle).
[0044] The hydrophobic treating agent 22 contained in the chemical
bottle 21 is temporarily fed to the hydrophobic atmosphere
producing agent 23 in accordance with a method such as nitrogen
pressure feed for blowing nitrogen into the chemical bottle 21.
Nitrogen is introduced into the hydrophobic atmosphere producing
section 23 supplied with the hydrophobic treating agent 22. At this
time, the nitrogen is blown into the inside of the hydrophobic
treating agent 22. It is desirable that the nitrogen introduced
into the hydrophobic atmosphere producing section 23 is nitrogen
with high purity. With such a design, an atmosphere including the
hydrophobic treating agent 22 is produced while bubbling is carried
out in the hydrophobic atmosphere producing portion 23. Thus, the
hydrophobic atmosphere producing section 23 is also referred to as
a bubbling section or a bubbling container.
[0045] A weight sensor 24 for sensing a capacity (weight) of the
hydrophobic treating agent 22 contained in the bubbling container
23 is installed at a bottom part (lower part) of the bubbling
portion 23. In the case where the hydrophobic treating agent 22
contained in the bubbling container 23 becomes equal to or smaller
than a predetermined quantity, the fact is sensed by the weight
sensor 24, and is notified to a control device (not shown). The
control device having received this notification is designed to
actuate a pump or the like (not shown) to automatically supply the
chemical 22 from the chemical bottle (hydrophobic treating agent
bottle) 21 into the bubbling container 23 until a predetermined
quantity has been reached.
[0046] The hydrophobic atmosphere produced at the bubbling portion
23 is pressure-fed to the hydrophobic treating agent inlet port
(hydrophobic atmosphere inlet port) 15 provided in the chamber 11
of the hydrophobic treatment section 10a described previously. The
pressure-fed hydrophobic atmosphere is introduced into the chamber
11 through the hydrophobic atmosphere inlet port 15.
[0047] As described above, the substrate processing apparatus 10
according to the embodiment is specifically provided as a
hydrophobic treatment apparatus for applying hydrophobic treatment
to the wafer 5, the apparatus including the hydrophobic treatment
section 10a and the hydrophobic treating agent supply device
10b.
[0048] Now, with reference to FIG. 4, a description will be given
with respect to a substrate processing method according to the
present embodiment. The substrate processing method according to
the embodiment is specifically provided as a hydrophobic treatment
method of a wafer 5.
[0049] First, as shown in FIG. 4, a wafer 5 having a diameter of
about 300 mm on which a resist film 32 or the like is not provided,
is housed in the above-described chamber 11. At this time, the
wafer 5 is placed on each pin 12 such that its surface 5a is
oriented upward and its back face 5c is oriented downward. The
wafer 5 is formed in an inclined shape such that the thickness is
reduced as its peripheral part 5b goes from the radial inside to
the radial outside of the wafer 5. Of the peripheral rim part 5b of
the wafer 5, a portion having such an inclination is provided is
referred to as a bevel portion 5d. In the embodiment, the wafer 5
is placed on each pin 12 while its back face 5c and bevel portion
5d are exposed.
[0050] Next, hydrophobic treatment is applied to the wafer 5 housed
in the chamber 11. Specifically, hydrophobic treatment is
selectively applied to the back face 5c and the bevel portion 5d of
the wafer 5. After the wafer 5 is housed in the chamber 11, the
atmosphere in the chamber 11 is evacuated from the exhaust port 17
to set the inside of the chamber 11 at a negative pressure.
Concurrently, a temperature of the hot plate 13 is adjusted such
that a temperature of the back face 5c of the wafer 5 is in the
range of about 80.degree. C. or more and 200.degree. C. or less. In
the embodiment, a gas between the back face 5c of the wafer 5 and a
surface (top face) of the hot plate 13 is set at about 3 mm.
[0051] Under such a design, the hydrophobic atmosphere described
previously is introduced into the chamber 11 via the hydrophobic
treating agent inlet port 15, so that a hydrophobic treatment is
started. As the hydrophobic treating agent 22, it is desirable to
use a silane coupling agent represented by hexamethyl disilazane
(HMDS) or the like. In the embodiment, hexamethyl disilazane (HMDS)
is used as the hydrophobic treating agent 22. Therefore, bubbling
is carried out with respect to the HMDS 22 supplied from the
chemical bottle 21 into the bubbling container 23 to produce the
atmosphere including the HMDS 22. Then, the atmosphere including
the HMDS 22 is introduced into the chamber 11 via the hydrating
processing agent inlet port 15. As the hydrophobic treating agent,
a fluorocarbon-based treating agent other than the HMDS 22 may be
used.
[0052] Thereafter, hydrophobic treatment is carried out at a
predetermined temperature for a predetermined time. Specifically,
it is desirable to set a temperature of the wafer 5 to be brought
into contact with the hydrophobic treating agent (HMDS) 22 at a
temperature ranging from a room temperature to about 200.degree. C.
The temperature of the wafer 5 may be determined in consideration
of, for example, a reaction temperature of the hydrophobic treating
agent 22 and a heat resistance of various coating films provided on
the wafer 5. It is desirable that a time required for hydrophobic
treatment is in the range of about 10 seconds to 300 seconds. In
this manner, the hydrophobic treatment according to the embodiment
is carried out by bringing water steam including the HMDS 22 into
contact with the wafer 5.
[0053] After hydrophobic treatment completes, an atmosphere
including the HMDS 22 is evacuated to the outside of the chamber 11
via the exhaust port 17. Subsequently, high purity N.sub.2 is
introduced into the chamber 11 via the intake port 16. After it is
verified that replacement of the hydrophobic atmosphere in the
chamber 11 has been sufficiently carried out, a shutter (not shown)
of the chamber 11 is opened. Then, the wafer 5 applied with
hydrophobic treatment is removed from the inside of the chamber
11.
[0054] In the present embodiment, it is desirable to apply
hydrophobic treatment such that a contact angle of pure water with
respect to the wafer 5 applied with hydrophobic treatment is equal
to or greater than about 45.degree.. In particular, it is desirable
to apply hydrophobic treatment such that a contact angle of pure
water with respect to the back face 5c and the bevel portion 5d of
the wafer 5 applied with hydrophobic treatment is equal to or
greater than 60.degree..
[0055] Next, as shown in FIG. 5B, an antireflection film 31 is
provided on the surface 5a of the wafer 5 applied with hydrophobic
treatment. The antireflection film 31 is formed in accordance with
a spin coat method by using, for example, a coating device (not
shown). That is, a coating material for the antireflection film is
dropped at the center part of the surface 5a of the rotating wafer
5, the dropped material is spread on the whole surface 5a, and
then, heat treatment is carried out. As a consequence, the
antireflection film 31 is formed on the surface 5a of the wafer 5.
In the embodiment, the antireflection film 31 having a film
thickness of about 80 nm is formed on the surface 5a of the wafer
5.
[0056] Next, as shown in FIG. 5B, a resist film 32 is formed on the
surface of the antireflection film 31. In the embodiment, an ArF
chemical amplification type resist film including an acid generator
agent is employed as the resist film 32. The resist film 32 is
formed in the same manner as the antireflection film 31. That is,
the coating material for the chemical amplification type resist
film 32 is spread on the antireflection film 31 in accordance with
a spin coat method. Subsequently, a solvent included in the coating
material is vaporized and eliminated by applying heat treatment to
the wafer 5 having the coating material for the chemical
amplification type resist 32 provided thereon. In this manner, the
ArF chemical amplification type resist film 32 is formed on the
surface of the antireflection film 31. In the embodiment, the ArF
chemical amplification type resist film 32 having a film thickness
of about 230 nm is provided on the surface 5a of the wafer 5.
[0057] Next, as shown in FIG. 5B, a liquid immersion exposure cover
film 33 that is soluble in a developer is formed on the surface of
the ArF chemical amplification type resist film 32. The cover film
33 is also formed in accordance with rotating coating and heat
treatment, as in the antireflection film 31 and the ArF chemical
amplification type resist film 32.
[0058] The wafer 5 having undergone the above process is shown in
FIGS. 5A and 5B. FIG. 5A is a plan view showing the wafer 5 having
the antireflection film 31, the ArF chemical amplification type
resist film 32, and the cover film 33 formed thereon, as seen from
the back face 5c. FIG. 5B is a sectional view showing the wafer 5
having the antireflection film 31, the ArF chemical amplification
type resist film 32, and the cover film 33 formed thereon.
[0059] As shown in FIGS. 5A and 5B, a hydrophobic-treated section
34 fully applied with hydrophobic treatment is formed on the back
face 5c of the wafer 5 such that a contact angle with pure water
becomes about 60.degree.. In addition, as shown in FIG. 5B, a
hydrophobic-treated section 34 is also formed at each of a side
part and a bottom face part of the bevel portion 5d of the
peripheral rim part (edge part) 5b of the wafer 5. The
antireflection film 31 is formed without overlapping the
hydrophobic-treated section 34 while covering the surface 5a of the
wafer 5 and a top face part of the bevel portion 5d of the wafer 5.
Similarly, the resist film 32 is also formed without overlapping
the hydrophobic-treated section 34 while covering the
antireflection film 31. The cover film 33 is formed with respect to
each of the films 31 and 32 while covering part of the
hydrophobic-treated section 34. Specifically, the cover film 33 is
formed while covering the hydrophobic-treated section 34 formed on
the antireflection film 31, the resist film 32, and the side face
part of the bevel portion 5d of the wafer 5.
[0060] Next, liquid immersion exposure treatment is applied to the
wafer 5 having the antireflection film 31, the ArF chemical
amplification type resist film 32, and the cover film 33. First,
the wafer 5 having the coating films 31, 32, and 33 formed thereon
is transported from the coating device to the liquid immersion type
exposure apparatus 1 described previously. Then, the wafer 5 is
placed on a wafer stage 6 of the exposure apparatus 1, and is held
by a support plate 7. Subsequently, alignment and alignment
exposure are carried out for the wafer 5. Then, in accordance with
liquid immersion exposure, a semiconductor element pattern
(reticule pattern), although not shown, formed on the reticule 2,
is transferred to the resist film 32 to form a latent image.
[0061] Next, the wafer 5 having such a latent image of a
semiconductor element pattern formed thereon is removed from the
top of the stage 6, and is transported from the exposure apparatus
1 into a chamber for post exposure baking (not shown). Then, heat
treatment (PEB) is applied to the wafer 5 at about 130.degree. C.
for about 60 seconds. This heat treatment promotes a dispersion
reaction and an amplification reaction of an acid generated in the
resist film in a liquid immersion exposure process (liquid
immersion exposure step).
[0062] Next, developing treatment is applied to the wafer 5 applied
with PEB. First, the wafer 5 applied with PEB is removed from the
inside of the PEB chamber, and the liquid immersion exposure cover
film 33 is released and eliminated from the top of the resist film
32. Subsequently, the wafer 5 having the cover film 33 removed
therefrom is transported to a developing treatment unit (not
shown).
[0063] When the wafer 5 is transported upward of a cup of the
developing treatment unit that holds the wafer 5, a pin first
rises, so that the wafer 5 is received. Then, the wafer 5 is placed
on a spin chuck to be vacuum-adsorbed. Subsequently, a nozzle that
is standby at a nozzle standby position ejects the developer toward
the wafer 5 while the nozzle moves above the wafer 5. In this
manner, the developer is applied onto the wafer 5 to perform
developing. Here, developing is carried out while the wafer 5 is
made still for about 30 seconds. After developing, pure water is
supplied onto the wafer 5 to wash out the developer. Then, the
wafer 5 is rotated, thereby carrying out swinging dry treatment. As
a consequence, a semiconductor element pattern (resist pattern),
although not shown, is formed on the resist film 32.
[0064] Thereafter, although a detailed and specific description
with illustration is omitted, the wafer 5 having a resist pattern
formed thereon is fed to a predetermined processing step. That is,
the wafer 5 having a resist pattern formed thereon is fed to
another Front End Of the Line (FEOL) such as a transistor
manufacturing process or a wiring forming process. Subsequently,
the wafer 5 having undergone FEOL is fed to a Back End Of the Line
(BEOL) such as dicing, chip mounting, bonding, and molding.
Undergoing the BEOL provides a desired semiconductor device (not
shown) according to the present embodiment. That is, there is
obtained a semiconductor device comprising the wafer 5 on which
hydrophobic treatment is applied to the back face 5d and the bevel
portion 5d by the hydrophobic treatment apparatus 10 prior to
forming the resist film 32.
[0065] In addition, although a detailed and specific description
with illustration is not shown, the inventors executed a prototype
experiment of forming wiring on the wafer 5 having undergone each
process. More specifically, a wiring pattern was formed on the
wafer 5 fabricated through the processes while the resist film 32
is used as a mask. As a result, a defect such as pattern
short-circuit was not found. A wiring pattern with its high
dimensional precision and good pattern shape can be obtained as
compared with a case of using a conventional wafer that is not
applied with hydrophobic treatment. That is, the present embodiment
can provide a semiconductor device having high device reliability,
quality, and performance etc. as compared with a semiconductor
device of a prior art. Concurrently, such a semiconductor device
can be manufactured efficiently and easily at a high yield.
[0066] Now, with reference to FIG. 6, a description will be given
with respect to Comparative Example of the present embodiment. FIG.
6 is a sectional view showing a wafer 101 according to Comparative
Example of the embodiment.
[0067] The wafer 101 is not applied with hydrophobic treatment,
unlike the above-described wafer 5 of the embodiment. An
antireflection film 102 is formed while covering a surface 101a and
a top face part of a bevel portion 101d of the wafer 101. A resist
film 103 is formed while covering the antireflection film 102. A
cover film 104 is formed while covering the antireflection film
102, the resist film 103 and a side face part of the bevel portion
101d of a peripheral rim part (edge part) 101b of the wafer
101.
[0068] The inventors performed liquid immersion exposure treatment
to the wafer 101 having such a constitution by using the liquid
immersion exposure apparatus 1 as in the present embodiment. Then,
after liquid immersion exposure treatment, the wafer 101 was
removed from the liquid immersion exposure apparatus 1 and
observed. Then, as shown in FIG. 6, water droplets of a liquid
immersion solution (pure water) 105 were deposited to a back face
101c and a bottom face part of the bevel portion 101d of the wafer
101, and were in a wet state.
[0069] As described in the Description of the Related Art section,
a danger of deteriorating quality of the wafer 101 becomes very
high if pure water 10 is rounded at the back face 101c of the wafer
101, and is in a wet state. Finally, there is a high danger that a
semiconductor device manufactured using the quality-degraded wafer
101 is lowered in its performance, quality, reliability and the
like.
[0070] In contrast, the wafer 5 according to the embodiment is
constituted so that, as described previously, hydrophobic treatment
is applied to the back face 5c and the bevel portion 5d by the
hydrophobic treatment apparatus 10 prior to providing the resist
film 32. For this reason, as shown in FIG. 5B, in the wafer 5
having completed liquid immersion exposure, water droplets are
hardly adhered to the top of the back face 5c and the top of the
bevel portion 5d as well as the top of the surface 5a. Accordingly,
there is almost no danger that the wafer 5 deteriorates in its
quality even if liquid immersion exposure is applied to the wafer
5. Finally, there is almost no danger that the performance,
quality, reliability and the like of the semiconductor device
according to the embodiment manufactured using the wafer 5 are
lowered. Although not shown, of course, hydrophobic treatment is
applied to the surface 5a of the wafer 5, according to the
previously described hydrophobic treatment.
[0071] Now, a description will be given with respect to a reason
for performing hydrophobic treatment prior to forming the resist
film 32.
[0072] What liquid immersion exposure is, in general, applied is a
generation that follows a so-called Deep UV lithography process
such as a KrF excimer laser lithography process and an ArF excimer
laser lithography process. A resist film called a chemical
amplification type resist film is used for a lithography process of
this generation. For example, a reaction mechanism in an exposure
process for the chemical amplification type resist film of a
positive type is as described below. First, when a resist film is
exposed, a photoacid generator agent included in the resist film
generates an acid. The generated acid decomposes after reacting
with a catalyst being a functional group referred to as a reaction
inhibition group that exists in the resist film. Consequently, a
resist film of an exposed portion becomes soluble to a
developer.
[0073] In the hydrophobic treatment process described previously, a
hydrophobic treating agent such as hexamethyl disilane is used.
However, in this case, a basal substance such as ammonia may be
generated as a byproduct in the resist film. If a byproduct made of
a basal substance is generated in the resist film, the byproduct
inhibits a catalytic reaction of the chemical amplification type
resist. Finally, the byproduct causes a shape failure of the resist
pattern.
[0074] Therefore, as described previously, hydrophobic treatment
for the wafer 5 must be carried out prior to forming the resist
film 32 on the wafer 5. In addition, it becomes possible to
eliminate a byproduct generated by hydrophobic treatment from the
surface 5a of the wafer 5 on which the resist film 32 is formed, by
adding heat treatment or the like.
[0075] As has described above, according to the first embodiment,
hydrophobic treatment is applied to at least the back face 5c and
the bevel portion 5d of the wafer 5 prior to forming the resist
film 32 on the wafer 5. In this manner, even if an immersion liquid
is rounded from the surface 5a to the back face 5c of the wafer 5
due to liquid immersion exposure, the back face 5c and bevel
portion 5d of the wafer 5 can be restricted from being wet.
Accordingly, there is almost no danger that the wafer 5
deteriorates in its quality even if liquid immersion exposure is
applied to the wafer 5. Finally, there is almost no danger that the
semiconductor device manufactured using the wafer 5 deteriorates in
its performance, quality, reliability and the like.
SECOND EMBODIMENT
[0076] Now, a second embodiment according to the present invention
will be described with reference to FIGS. 7A and 7B. FIGS. 7A and
7B are respectively a plan view and a sectional view showing a
substrate applied with substrate processing according to the second
embodiment, as seen from a back face. Like constituent elements in
the first embodiment are designated with like reference numerals,
and a detailed description is omitted here.
[0077] In the second embodiment, unlike the first embodiment
described above, hydrophobic treatment is not applied to the whole
back face 5c of the wafer 5. In the second embodiment, hydrophobic
treatment is selectively applied to a region enclosed in a
predetermined range from the peripheral rim part 5b, of the back
face 5c of the wafer 5. Now, a specific and detailed description
will be given below.
[0078] First, in the second embodiment, as indicated by the dashed
line shown in FIG. 2, a hydrophobic treating agent shielding
mechanism 14 is installed while covering the center part 5e of the
back face 5c of the wafer 5. The hydrophobic treating agent
shielding mechanism 14 is located at a position opposite to the
center part 5e of the back face 5c of the wafer 5 in the chamber 11
of the hydrophobic treatment apparatus 10 for use in the first
embodiment. That is, the hydrophobic treating agent shielding
mechanism 14 is installed at the periphery of the hot plate 13. The
hydrophobic treating agent shielding mechanism 14 is specifically
provided as a shielding plate having a width of 3 mm. Concurrently,
a plurality of spacer members (gap spacers) 41 having a size of
about 100 .mu.m are provided on a main face at a side of the
shielding plate 14 opposite to a back face 5c of the wafer 5. The
wafer 5 housed in the chamber 11 is placed on each of the gap
spacers 41 arranged between these shielding plate 14 and the back
face 5c of the wafer 5. In this manner, a hydrophobic atmosphere is
inhibited from coming into contact with the center part 5e of the
back face 5c of the wafer 5. Under such a design, hydrophobic
treatment is applied to the wafer 5 in the same manner as in the
first embodiment. In the second embodiment, hydrophobic treatment
is applied to the wafer 5 at about 100.degree. C. for about 10
seconds. Other processes are similar to those according to the
first embodiment.
[0079] The wafer 5 having undergone the above process is shown in
FIGS. 7A and 7B. FIG. 7A is a plan view showing the wafer 5 having
the antireflection film 31, the ArF chemical amplification type
resist film 32, and the cover film 33 formed thereon, as seen from
the back face 5c. FIG. 7B is a sectional view showing the wafer 5
the antireflection film 31, the ArF chemical amplification type
resist film 32, and the cover film 33 formed thereon.
[0080] As shown in FIGS. 7A and 7B, hydrophobic treatment is
applied to a region excluding its center part 5e, so that a
hydrophobic-treated section 34 is formed on the back face 5c of the
wafer 5. However, as shown in FIG. 7, as in the first embodiment, a
hydrophobic-treated section 34 is formed at a side part and a
bottom face part of the bevel portion 5d at the peripheral rim part
(edge part) 5b of the wafer 5. Then, as shown in FIG. 7B, the
antireflection film 31, the resist film 32, and the cover film 33
are formed in constitution similar to that according to the first
embodiment.
[0081] In a general liquid immersion type exposure apparatus,
including the liquid immersion type exposure apparatus used in the
first embodiment, a water discharge device (water absorption
mechanism) for removing an immersion liquid from a wafer stage is
provided at a portion adjacent to an edge part of a wafer on the
wafer stage. Thus, while at least liquid immersion exposure is
carried out, there is almost no danger that a center part of a back
face of the wafer comes into contact with an immersion liquid.
Accordingly, unlike the first embodiment, it is not always
necessary to fully apply hydrophobic treatment to the back face 5c
of the wafer 5. It suffices that hydrophobic treatment is applied
to a region and its outside of the back face 5c and peripheral rim
part 5b of the wafer 5, in which water absorption of an immersion
liquid is carried out by the water adsorption mechanism. That is,
as in the present embodiment, it suffices that hydrophobic
treatment is applied to the peripheral rim part 5b of the back face
5c of the wafer 5 and the bevel portion 5d of the wafer 5 excluding
the center part 5e, of at least the back face 5c of the wafer
5.
[0082] As has been described above, according to the second
embodiment, advantageous effect similar to the above-described
first embodiment can be obtained.
THIRD EMBODIMENT
[0083] Now, a third embodiment according to the present invention
will be described with reference to FIG. 8. FIG. 8 is a flow chart
showing a substrate processing method according to the third
embodiment. Like constituent elements in the first and second
embodiments are designated by like reference numerals, and a
detailed description is omitted here.
[0084] In the third embodiment, unlike the first and second
embodiments, an antireflection film 31 is formed on a surface 5a of
the wafer 5 prior to applying hydrophobic treatment to the wafer 5.
Now, a brief description will be given below.
[0085] As shown in FIG. 8, unlike the first and second embodiments,
the organic antireflection film 31 is provided on the surface 5a of
the wafer 5 prior to applying hydrophobic treatment to the wafer 5
in the present embodiment. Then, hydrophobic treatment is applied
to the wafer 5 having the organic antireflection film 31 formed
thereon. Further, prior to forming a resist film 32 on the organic
antireflection film 31, heat treatment is applied to the wafer 5
applied with hydrophobic treatment. Other processes are identical
to those according to the first embodiment.
[0086] As has been described in the first embodiment, in the case
where hydrophobic treatment is applied to the wafer 5, care must be
taken for the generation of a byproduct due to the hydrophobic
treatment. That is, there is a need for taking an account into
contamination of the organic antireflection film 31 due to a
byproduct. If the organic antireflection film 31 is contaminated by
the byproduct, there is a high danger that a failure occurs with a
shape of a resist pattern when the resist pattern is formed on the
resist film formed on the organic antireflection film 31. In order
to restrict a shape failure of such a resist pattern, a
contamination substance may be removed from the inside of the
organic antireflection film 31 prior to forming the resist film 32
on the organic antireflection film 31. In the third embodiment, as
shown in FIG. 8, heat treatment is applied to the wafer 5 applied
with hydrophobic treatment, prior to forming the resist film 32 on
the organic antireflection film 31. As a consequence, contamination
substances (impurities) that cause a shape failure of a resist
pattern are removed in advance from the inside of the
antireflection film 31, prior to forming the resist film 32 on the
organic antireflection film 31.
[0087] A detailed and specific description with illustration is not
shown. According to embodiment carried out by the inventors, a
prototype test for forming wiring on the wafer 5 fabricated by the
present embodiment was carried out. That is, with respect to the
wafer 5 fabricated through the processes shown in FIG. 8, a wiring
pattern was formed with the resist film 32 being a mask. As a
result, a defect such as a pattern short-circuit was not found.
Successfully, a wiring pattern having high dimensional precision
and good pattern shape could be obtained as compared with a case of
using a conventional wafer that is not applied with hydrophobic
treatment.
[0088] As has been described above, according to the third
embodiment, it is possible to attain an advantageous effect that is
similar to those according to the first and second embodiments.
[0089] The substrate processing method and substrate processing
apparatus according to the invention are not restricted to those in
the first to third embodiments. Without deviating from the spirit
of the present invention, part of these constituent elements or
manufacturing steps can be changed to a variety of settings or
various setting can be provided using them in proper
combination.
[0090] For example, hydrophobic treatment relevant to the wafer 5
is not always limited to gaseous hydrophobic treatment atmosphere
(hydrophobic treatment evaporation) including the hydrophobic
treating agent 22. Instead of a gaseous hydrophobic treatment
atmosphere, a liquid containing the hydrophobic treating agent 22
may be directly supplied to a portion of the wafer 5 that requires
hydrophobic treatment.
[0091] The hydrophobic treating agent 22 is not always limited to a
silane coupling agent represented by hexamethyl disilane (HMDS) or
the like. As the hydrophobic treating agent 22, for example, an
organic silicon compound or a fluorocarbon-based compound may be
used.
[0092] In addition, heat treatment (PEB) relevant to the wafer 5
applied with hydrophobic treatment does not always need to be
carried out at about 130.degree. C. It suffices that heat treatment
relevant to the wafer 5 applied with hydrophobic treatment is
carried out at about 100.degree. C. or more.
[0093] The gap (proximal distance) between the shielding plate 14
and the back face 5c of the wafer 5 in the second embodiment is not
always limited to about 100 .mu.m. The gap between the shielding
plate 14 and the back face 5c of the wafer 5 may be equal to or
smaller than about 500 .mu.m. That is, the gap between the
shielding plate 14 and the back face 5c of the wafer 5 may be set
in size such that a hydrophobic treating agent can come into
contact with the center part 5e of the back face 5c of the wafer 5.
As long as the gap between the shielding plate 14 and the back face
5c of the wafer 5 is equal to or smaller than about 500 .mu.m, the
back face 5c of the wafer 5 may be properly made proximal to the
shielding plate 14 at a proper gap. Alternatively, the back face 5c
of the wafer 5 may be brought into contact with the shielding plate
14. That is, the gap between the shielding plate 14 and the back
face 5c of the wafer 5 may be 0 .mu.m. In addition, adjustment of
the gap between the shielding plate 14 and the back face 5c of the
wafer 5 is not always limited to a method for providing the gap
spacer 41 formed in advance in desired size on the upper part of
the shielding plate 14, as described previously. The gap between
the shielding plate 14 and the back face 5c of the wafer 5 may be
adjusted such that, for example, each pin 12 is movable in a
longitudinal direction (vertical direction), or may be set by
elevating each of these pins.
[0094] Portions to be applied with hydrophobic treatment are not
limited to the portions described previously. It suffices that
hydrophobic treatment is applied to at least one of the bevel
portion 5d and the back face 5c that is outer than a film (coat
film) for coating the outermost part of at least the outer
periphery part of the wafer 5. Specifically, assume that a wiring
pattern or the like is subjected to liquid immersion exposure by
using the liquid immersion exposure apparatus 1 with respect to the
resist film 32 of the wafer 5 on which the surface 5a of the wafer
5 that is a main face at a side having a semiconductor element
formed thereon is approximately covered with various coat films
such as the antireflection film 31, the resist film 32, and the
liquid immersion cover film 33. In this case, it suffices that the
back face 5c of the wafer 5 that is not covered with a coat film is
hydrophobized in advance. In addition, when the wafer 5 is held in
a process other than the hydrophobic treatment process, such as a
liquid immersion exposure process, it is desirable that a holding
mechanism for holding the wafer 5 should not come into contact with
a region of the wafer 5 applied with hydrophobic treatment.
[0095] A film structure on the wafer 5 is not limited to the
structure described previously. For example, after a hard mask
composed of an inorganic film for processing the wafer 5 is first
formed on the wafer 5, an organic antireflection film 31 may be
formed thereon. In this case, hydrophobic treatment may be carried
out after the hard mask is formed.
[0096] In addition, a structure of the resist film 32 is not
limited to the single-layered structure described previously. For
example, after a lower layer resist film and an intermediate resist
film are properly formed on the wafer 5, a resist film having a
multi-layered structure may be provided on the wafer 5 in
accordance with a multi-layered resist process for forming an
upper-layered resist film. In this case, it is desirable to carry
out hydrophobic treatment before any one of the process for forming
a lower-layered resist film, the process for forming a intermediate
resist film, and the process for forming an intermediate resist
film, and the process for forming an upper-layered resist film. As
required, it is desirable to add heat treatment as additional
processing before any one of these processes, as in the third
embodiment in which the organic antireflection film 31 is provided
on the wafer 5 prior to carrying out hydrophobic treatment.
[0097] Further, either of an organic film and an inorganic film may
be used as the antireflection film 31. Concurrently, the
antireflection film 31 may be formed in a multi-layered structure
such that a same type or different type of reflection film films
are formed in a plurality of layers.
[0098] In the case where an inorganic antireflection film such as a
SiON film formed in accordance with a chemical vapor deposition
(CVD) method is used as the antireflection film 31, the inorganic
antireflection film is occasionally formed on the back face 5c of
the wafer 5. In this case, liquid immersion exposure is carried out
with the back face 5c of the wafer 5 covered with an inorganic
antireflection film. In such a case, hydrophobic treatment for the
wafer 5 needs to be carried out after forming an inorganic
antireflection film and before forming a resist film.
[0099] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *